According to the mobile analytics firm Flurry, phablets with screens measuring between 5 and 6.9 inches like the iPhone Plus saw the biggest increase in activations during the week between December 19 and December 25.That jump likely came at the expense of medium-sized phones 3.5- to 4.9-inch phones , like the regular iPhone, which continued to see its market share decrease over the past three years.

All other devices mostly remained flat year-over-year.Medium-sized smartphones still saw the most activations during the week leading up to the holidays.

But as Flurry points out, phablets may end up becoming the "dominant form factor" very soon.

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